Computing devices such as personal computers, laptop computers, tablet computers, cellular phones, and countless types of Internet-capable devices are increasingly prevalent in various aspects of modern life. As computers become more advanced, augmented-reality devices, which blend computer-generated information with a user's perception of the physical world, are expected to become more common.
To provide an augmented-reality experience, location and context-aware computing devices may be worn by a user as they go about various aspects of their everyday life. Such computing devices, which are commonly referred to as “wearable” computers, are configured to sense and analyze a user's environment, and to intelligently provide information appropriate to the physical world as it is experienced by the user. Such wearable computers may sense a user's surrounding by, for example, determining a user's geographic location, using cameras and/or sensors to detect objects within the user's field of vision, using microphones and/or sensors to detect what a user is hearing, and using various other sensors to collect information about the environment surrounding the user. Further, wearable computers may use biosensors to detect the user's own physical state. The information collected by the wearable computer may then be analyzed in order to determine what information should be presented to the user.
Many wearable computers include or take the form of a head-mounted display (HMD) that is worn by the user. An HMD typically provides a heads-up display near to the user's eyes. As such, HMDs may also be referred to as “near-eye” displays. HMDs typically overlay computer-generated graphics (e.g., text, images, video, etc.) on the physical world perceived by the user. HMDs may include some form of display that renders graphics in front of one or both of the user's eyes in such a manner that the user perceives the computer-generated graphics and the physical world simultaneously. HMDs that include displays in front of both of the user's eyes are referred to as “binocular” HMDs, while those that include a display in front of just one eye are referred to as “monocular” HMDs.
HMDs may integrate computer-generated graphics in the user's view of the physical world using a number of techniques. For example, “see-through” HMDs may display graphics on a transparent surface so that the user sees the graphics overlaid on the physical world. As another example, “see-around” HMDs overlay a display on the physical world by placing the display close to the user's eye in order to take advantage of the “sharing” of vision between a user's eyes and create the effect of the display being part of the world seen by the user.
In order to sense a user's environment, a wearable computer may include a “point-of-view” video camera that is aligned with the user's frame of reference and mounted so as to track movement of the user's head. By effectively capturing what the user is seeing at a given point in time, this video can be analyzed to detect objects and/or people within the user's view, to identify these objects and/or people, and to display information in the HMD that corresponds to these objects and/or people. Furthermore, analysis of the video may be used to determine where a given object or person is located in the user's frame of reference, and to display corresponding information in the HMD such that the user sees the corresponding information as “floating” over or near the given object or person.
As an example, when a user is looking at a friend, a video camera on the user's HMD may capture video of the friend. The video can then be analyzed using, for example, well-known facial recognition techniques. As such, the friend may be identified, and information related to the friend may be displayed so that the user sees the information proximate to their friend. For example, the HMD may display the friend's name, contact information, birthday, etc.